Are you going to use multiple gpus ? Then the x58/lga1336 will be the best choice. Even if I had to use 1 gpu, I'd still get the lga1336 board, just because it is superior, and as far as I know, it will support the new i7's with 6 cores.
The LGA1366 would be your best bet since video editing programs like two things: More cores and more memory bandwidth.
LGA1366 has three channels of DDR3 so it will boost the bandwidth memory wise as well as support the 6 core CPUs and I have heard it may support the 12 core CPUs if they hit for the consumer end.
socket 1366 board, i7 920 CPU and overclock it, 12GB 1600MHz RAM (CAS7 if you can stretch it, or good quality CAS8 and tighten it) and you're away.
If you're working with Adobe CS4 I'd recommend getting an NVIDIA graphics cards (GTX250 or GTX260) because CS4 does like its CUDA (if you can find the CUDA H.264 encoder that comes with the Quadro CX it's MINT) and I've had more stability with CS4's GPU acceleration on NVIDIA cards.